antlr-3.4/runtime/ActionScript/project/src/org/antlr/runtime/TokenSource.as

/*
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 Copyright (c) 2005-2006 Terence Parr
 All rights reserved.

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    derived from this software without specific prior written permission.

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package org.antlr.runtime {
	/** A source of tokens must provide a sequence of tokens via nextToken()
	 *  and also must reveal it's source of characters; CommonToken's text is
	 *  computed from a CharStream; it only store indices into the char stream.
	 *
	 *  Errors from the lexer are never passed to the parser.  Either you want
	 *  to keep going or you do not upon token recognition error.  If you do not
	 *  want to continue lexing then you do not want to continue parsing.  Just
	 *  throw an exception not under RecognitionException and Java will naturally
	 *  toss you all the way out of the recognizers.  If you want to continue
	 *  lexing then you should not throw an exception to the parser--it has already
	 *  requested a token.  Keep lexing until you get a valid one.  Just report
	 *  errors and keep going, looking for a valid token.
	 */
	public interface TokenSource {
		/** Return a Token object from your input stream (usually a CharStream).
		 *  Do not fail/return upon lexing error; keep chewing on the characters
		 *  until you get a good one; errors are not passed through to the parser.
		 */
		function nextToken():Token;
		
		/** Where are you getting tokens from? normally the implication will simply
		 *  ask lexers input stream.
		 */
		function get sourceName():String;
	}
}